Thrombin is known to have a variety of activities in different cell types. PAR-1 receptors are known to be present in such cell types as human platelets, vascular smooth muscle cells, endothelial cells and fibroblasts. The art indicates that PAR-1 receptor antagonists would be expected to be useful in the treatment of thrombotic, inflammatory, atherosclerotic and fibroproliferative disorders, as well as other disorders in which thrombin and its receptor play a pathological role.
Thrombin receptor antagonist peptides have been identified based on structure-activity studies involving substitutions of amino acids on thrombin receptors. In Bernatowicz et al., J. Med. Chem., 39 (1996), p. 4879-4887, tetra- and pentapeptides are disclosed as being potent thrombin receptor antagonists, for example N-trans-cinnamoyl-p-fluoroPhe-p-guanidinoPhe-Leu-Arg-NH2 and N-trans-cinnamoyl-p-fluoroPhe-p-guanidinoPhe-Leu-Arg-Arg-NH2. Peptide thrombin receptor antagonists are also disclosed in WO 94/03479.
Cannabinoid receptors belong to the superfamily of G-protein coupled receptors. They are classified into the predominantly neuronal CB1 receptors and the predominantly peripheral CB2 receptors. These receptors exert their biological actions by modulating adenylate cyclase and Ca+2 and K+ currents. While the effects of CB1 receptors are principally associated with the central nervous system, CB2 receptors are believed to have peripheral effects related to bronchial constriction, immunomodulation and inflammation. As such, the art suggests that a selective CB2 receptor binding agent might be expected to have therapeutic utility in the control of diseases associated with rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, diabetes, osteoporosis, renal ischemia, cerebral stroke, cerebral ischemia, nephritis, inflammatory disorders of the lungs and gastrointestinal tract, and respiratory tract disorders such as reversible airway obstruction, chronic asthma and bronchitis (R. G. Pertwee, Curr. Med. Chem. 6(8), (1999), 635; M. Bensaid, Molecular Pharmacology, 63 (4), (2003), 908).
Himbacine, a piperidine alkaloid of the formula
has been identified as a muscarinic receptor antagonist. The total synthesis of (+)-himbacine is disclosed in Chackalamannil et al., J. Am. Chem. Soc., 118 (1996), p. 9812-9813.
Substituted bi- and tricyclic thrombin receptors antagonists are known in the art to treat thrombin receptor mediated disorders such as thrombosis, atherosclerosis, restenosis, hypertension, angina pectoris, angiogenesis related disorders, arrhythmia, a cardiovascular or circulatory disease or condition, heart failure, ACS, myocardial infarction, glomerulonephritis, thrombotic stroke, thromboembolytic stroke, PAD, deep vein thrombosis, venous thromboembolism, a cardiovascular disease associated with hormone replacement therapy, disseminated intravascular coagulation syndrome and cerebral infarction, as well as CB2 receptor mediated disorders. U.S. Pat. No. 6,645,987 and U.S. Pat. No. 6,894,065 disclose PAR-1 receptor antagonists of the structure:
where R10 may be groups such as H, alkyl, haloalkyl, hydroxyl, etc. and R22 may be groups such as H, optionally substituted alkyl, hydroxyl, etc. Other known substituted thrombin receptor antagonists are disclosed in WO2001/96330, U.S. Pat. No. 6,063,847, U.S. Pat. No. 6,326,380, U.S. Pat. No. 7,037,920, U.S. Pat. No. 7,488,742, U.S. Pat. No. 7,713,999, U.S. Pat. No. 7,442,712, U.S. Pat. No. 7,488,752, U.S. Pat. Nos. 7,776,889, 7,888,369, U.S. Pat. No. 8,003,803 and U.S. Pat. No. 8,022,088. US 2008/0090830 and Chackalamannil et al., J. Med. Chem., 49 (2006), p. 5389. A PAR-1 receptor antagonist that exhibits good thrombin receptor antagonist activity (potency) and selectivity is vorapaxar (Merck & Co., Inc.), which has the following structure:
This compound underwent clinical trials and is disclosed in U.S. Pat. No. 7,304,048. A crystalline form of the bisulfate salt of vorapaxar is disclosed in U.S. Pat. No. 7,235,567.
WO2011/162,562 to LG Life Sciences LTD. describes a series of [6+5] fused bicycle derivatives of the general structure:
where R5 and R6 are inter alia both fluoro groups, as inhibitors of the PAR-1 receptor. The compounds are taught to be useful in the treatment and prevention of thrombus, platelet aggregation, atherosclerosis, restenosis, blood coagulation, hypertension, arrhythmia, angina pectoris, heart failure, inflammation and cancer when used alone or with other cardiovascular agents.
WO2011/28420 and WO2011/28421, both to Sanofi-Aventis, disclose compounds that are reported to be PAR-1 receptor antagonists. The compounds disclosed in WO2011/28420 are pyridyl-vinyl pyrazoloquinolines derivatives and have the following general structure:
WO2011/28421 discloses tryicyclic pyridyl-vinyl-pyrrole derivatives of the following general structure:
PCT/US13/027383 to Merck Sharp and Dohme, Corp. discloses bicyclic himbacine derivatives of the following general structure
where R10 and R11 may both be fluoro groups. These compounds are PAR-1 receptor antagonists.
Applicants discovered in accordance with the present invention that the inventive compounds act as inhibitors of PAR-1 receptor and, based upon their structure, might also act as inhibitors of the CB2 receptor. Therefore, the inventive compounds might be expected to be useful in treating disease states associated with the inhibition of these receptors.
There is a need for new compounds, formulations, treatment and therapies to treat diseases associated with the PAR-1 and CB2 receptors. Moreover, there is a need to develop therapeutics that exhibit improved therapeutic profiles; for example, desirable half-life or reduced unintended effects, such as not causing drug induced (acquired) long QT syndrome, which potentially can be fatal, or reduced drug-drug interactions (DDIs). DDIs are potentially undesirable as they can reduce the therapeutic effectiveness of an agent or increase the incidence of unintended effects associated with the drug. It is, therefore, an object of this invention to provide compounds useful in the treatment, prevention or amelioration of such diseases or disorders with improved therapeutic profiles. These and other objectives will become evident from the following description.